Estimating winter wheat yield from hyperspectral data

Spectral data are strongly related to canopy parameters, which are related to final yield at a critical stage of the crop growth, so it is possible to estimate wheat yield from spectral data. In this paper, firstly, the yield data were related to the field hyperspectral reflectance data in 8 different growth stages from regreening stage to milking stage. The statistical results show that yield is positive correlative with spectral reflectance in NIR bands and negative correlative in visible and SWIR bands. Secondly, the normalized difference spectral indices defined by [860 nm, 1200 nm], [890 nm, 980 nm], [820 nm, 1650 nm], [820 nm, 1650 nm] and [820 nm, 2200 nm] are designed and related to yields in all the 8 growth stages. Compared with NDVI, these spectral indices can predict yield earlier and more reliably. Finally, the remote sensing models in different growth stages for yield were built by [820 nm, 1650 nm] weak water absorption index.